In the related art, there is a known robot system in which, in order to prevent an excessive external force from acting on a robot, the magnitude of an external force acting on the robot is detected by a force sensor, and the robot is controlled on the basis of the detected magnitude of the external force (for example, see Japanese Unexamined Patent Application, Publication No. 2016-64474 and Japanese Unexamined Patent Application, Publication No. Hei 04-344505).
The robot system disclosed in Japanese Unexamined Patent Application, Publication No. 2016-64474 is a cooperative robot system working with a human in a common workspace, detects contact of a robot with the human or a surrounding object by using a force sensor, and stops the robot when the magnitude of a detected external force exceeds a predetermined threshold.
The robot system disclosed in Japanese Unexamined Patent Application, Publication No. Hei 04-344505 is a direct-teaching robot system in which a hand of a robot is directly operated by a human, detects a force applied by the human to the hand of the robot by using a force sensor, and stops the robot or issues a warning when the magnitude of the detected external force exceeds a predetermined threshold.